Photodegradation of PCL was performed exposing injected specimens to ultraviolet radiation (UV-B) up to 9 weeks. Photodegradated PCL specimens were tested by Differential Scanning Calorimetry (DSC), Infrared Spectroscopy (FTIR), mechanical properties, Optical Microscopy (MO) and Scanning Electron Microscopy (SEM).Upon exposure decrease in elongation at break and increase of elastic modulus were verified, higher degree of crystallinity was observed for longer exposure what can be due to the chemi-crystallization mechanism. From IR spectra new carbonyl group (C=O) peaks were observed. Presence of micro cracks on specimens' surface was identified by MO. From morphological analyses is suggested that the photodegradation in PCL takes place by bulk erosion mechanism.

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This research aimed to evaluate the influence of styrene–butadiene–styrene (SBS) compatibilizer in the polystyrene blends properties with a recycled styrene–butadiene rubber compound. The SBS content was 5, 7.5, and 10%. Commercial high-impact polystyrene (HIPS) was used for comparison. The results indicated that the viscosity of the blends was higher than that of HIPS. The blends compatibilized with 5 and 7.5% had the same level of impact strength as HIPS, while the one with 10% obtained a gain of 80% in relation to HIPS. The flexural strength, hardness, heat deflection temperature, and Vicat softening temperature properties were similar to those of HIPS, which was attributed to the presence of inorganic fillers, minimizing losses in these properties. By atomic force microscopy, two distinct phases were observed, and in the morphology analyzed through scanning electron microscopy, a typical characteristic of immiscible blends was observed.

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